fis-gtm/sr_port/time_calc.c

116 lines
2.9 KiB
C

/****************************************************************
* *
* Copyright 2001 Sanchez Computer Associates, Inc. *
* *
* This source code contains the intellectual property *
* of its copyright holder(s), and is made available *
* under a license. If you do not know the terms of *
* the license, please stop and do not read further. *
* *
****************************************************************/
/*
* --------------------------------------------------------------
* This file contains system independent routines for time handling
* --------------------------------------------------------------
*/
#include "mdef.h"
#include "gt_timer.h"
/*
* ----------------------------------
* Compare 2 absolute times
*
* Return:
* -1 - atp1 < atp2
* 0 - atp1 = atp2
* 1 - atp1 > atp2
* ----------------------------------
*/
int4 abs_time_comp(ABS_TIME *atp1, ABS_TIME *atp2)
{
if (atp1->at_sec > atp2->at_sec)
return (1);
if (atp1->at_sec < atp2->at_sec)
return (-1);
if (atp1->at_usec == atp2->at_usec)
return (0);
if (atp1->at_usec > atp2->at_usec)
return (1);
return (-1);
}
/*
* ---------------------------------------------------------------------
* Add integer to absolute time
* Absolute time structure is seconds & microseconds.
* Integer value is in milliseconds.
*
* Arguments:
* atps - source time structure
* ival - integer to be added to source structure (milliseconds)
* atpd - destination time structure
* ---------------------------------------------------------------------
*/
void add_int_to_abs_time(ABS_TIME *atps, int4 ival,ABS_TIME *atpd)
{
int4 ival_sec, ival_usec;
error_def (ERR_TIMEROVFL);
if (ival < 0)
{
/* Negative values won't work properly; they're probably
* also an indication of arithmetic overflow when
* multiplying by 1000 to convert from seconds to
* milliseconds.
*/
rts_error(VARLSTCNT(1) ERR_TIMEROVFL);
}
ival_sec = ival / 1000; /* milliseconds -> seconds */
ival_usec = (ival - (ival_sec * 1000)) * 1000; /* microsecond remainder */
atpd->at_sec = atps->at_sec + ival_sec;
if ((atpd->at_usec = atps->at_usec + ival_usec) >= 1000000)
{
/* microsecond overflow */
atpd->at_usec -= 1000000;
atpd->at_sec += 1; /* carry */
}
}
/*
* ------------------------------------------------------
* Substract absolute time atp2 from absolute time atp1
* Absolute time structure is seconds & microseconds.
* Integer value is in milliseconds.
*
* Arguments:
* atp1 - source time structure
* atp2 - destination time structure
*
* Return:
* difference time structure
* ------------------------------------------------------
*/
ABS_TIME sub_abs_time(ABS_TIME *atp1, ABS_TIME *atp2)
{
ABS_TIME dat;
int4 ival;
dat.at_sec = atp1->at_sec - atp2->at_sec;
dat.at_usec = atp1->at_usec - atp2->at_usec;
if (atp2->at_usec > atp1->at_usec)
{
dat.at_usec += 1000000;
dat.at_sec--;
}
return (dat);
}